1. Field of the Invention
The present invention relates generally to a snow guard system capable of being attached to a roof, which is used to prevent snow from sliding off the roof, and more particularly to an improved flag for attachment to a pipe employed in such snow guard systems to better restrain snow from sliding off the roof.
2. Related Art
Sliding snow and/or ice from roofs can be hazardous to people, the surrounding landscape, property, and building components. The problem of sliding snow or ice is particularly prevalent in connection with metal roofs, including raised seam roofs, where there is relatively little friction between the roof and the snow or ice. To combat this problem, guards have been developed for controlling movement of snow and ice across selected areas of roofs by preventing sliding of snow and ice down the pitch of the roof.
These snowguard systems have long been used to control the movement of snow and ice located on roofs, for example, see U.S. Pat. No. 42,972 to Howe, which issued May 31, 1864. Recently, these snow guard systems have increased in popularity, and currently several snowguard mounting systems serve to hold snowloads on roofs.
FIG. 1 shows an example of one such snow guard system, as described in detail in applicant""s U.S. Pat. No. 5,613,328, the entirety of which is incorporated herein by reference. As shown in FIG. 1, the snow guard comprises blocks 100, each having a groove, or other suitable opening, located in the base thereof. The blocks are attached to the metal roof by placing the groove about a segment of the seams in the metal roof. Each block further has a groove, or other suitable opening, located in the top thereof, for holding brackets 101. The brackets have a plurality of holes located therein, allowing round pipes 102 to be placed therethrough. The pipes help to secure snow which might accumulate on the roof, thereby preventing it from falling off the roof and potentially injuring persons or damaging property located in its fall path.
In an effort to further improve the snow restraining capabilities of the above mentioned snow guard, artisans have previously affixed a one-piece curled vertical flag 103 to the horizontal pipes, as shown in FIG. 2. The specific shape of flag 103 is shown in FIGS. 3A, 3B, and 3C. The upper portion of flag 103 rests on the upper horizonal pipe, and is prevented from rotating in the direction of the snow load by the lower second horizontal pipe. These vertical flags allow the snow load to be restrained more effectively compared to the use of horizontal piping alone. Moreover, since the bottom of the flags is spaced from the roof, they still allow a portion of the snow load to fall from the roof, to thereby prevent the snow from accumulating to dangerous levels.
However, there are a number of drawbacks generally associated with the snow guards described above. One particular drawback relates to the flags, in that they usually are not securely attached to the pipes. As a result, the flags can fall off when caused to rotate by some external disturbance. In particular, the flags can be blown off of the pipes when there is no snow load, by wind gusts traveling in directions opposite to the snow load, (i.e., from the eaves to the peak of the roof).
Additional securing means 104 are sometimes provided to hold the flags on the pipes. However, the securing means do not entirely prevent rotation of the flags when subjected to a disturbance. As a result, the flags can still rotate around the circular pipe, so that the bottom of the flag rests on the downstream side of the lower pipe. Thereafter, the flag cannot perform its intended function (i.e., the lower pipe no longer stands behind the bottom portion of the flag to restrain the snow load).
Another problem with flags that use securing means is that they are more expensive to manufacture and more difficult to install. Specifically, the securing means is an additional component that takes more time to make and more time to install on the roof. Due to the height of roofs that typically require snow guard systems, the installation crew would like to minimize the amount of time and effort they spend while on the roof itself. The current snow guard systems, however, do not allow fast and easy installation.
It is an object of the present invention to overcome the above-discussed drawbacks associated with prior art snow guard systems.
To carry out the objects described above, one embodiment of the present invention is directed to a device for use as a component part of a snowguard system for preventing materials from sliding off a roof. The device comprises a mounting bracket having a bracket portion with at least one bore defining at least one cutout region therethrough. The cutout region has a circumferential shape. At least one pipe is slidably insertable through the bore and has a circumferential shape substantially similar to that of the cutout region. Interaction between the two shapes prevents rotation of the pipe relative to the bracket. The device also includes at least one flag having an interior portion whose shape is substantially geometrically similar to at least a portion of the circumferential shape of the pipe, thereby allowing the interior portion of the flag to lockingly engage the exterior of the pipe, without being able to rotate with respect to the pipe (and bracket).
Preferably, the circumferential shape of the pipe is non-circular to prevent rotation of the flag relative to the pipe and, in turn, to prevent rotation of the pipe relative to the bracket. For instance, a D-shaped cross-section, a polygonal shaped cross-section, an elliptical shaped cross-section, a parabolic shaped cross-section, or a truncated cone shaped cross-section could be used for the pipe and cut-out region of the bracket.
The flag can have any shape which allows for attachment to the pipe. The most important thing is that the flag is self-locking on the pipe without any additional attachment mechanism (although one could be used in an overabundance of caution). In a preferred embodiment the flag has an inverted, vertical J-shape.
The bore and the pipe should be oriented such that an axis of symmetry of the pipe is substantially perpendicular to the direction of the force exerted by a load thereon. This allows the pipe to withstand maximum tensile and compressive stresses caused by the load.
The pipe may optionally include at least one diametrical reinforcement member on its interior. This reinforcement member should be oriented to provide maximum resistance to the load exerted thereon. In a preferred embodiment, the diametrical reinforcement member is web-like in cross-section.
In addition, the mounting bracket can be one piece or comprised of separate pieces. For example, the mounting bracket can comprise a mounting block and a bracket portion, in which the mounting block has a first groove in the upper surface thereof for slidably receiving the bracket portion, and in which the mounting block has a second groove in the lower surface thereof for attachment to the seam of a metal roof.
Additional objects, advantages, and other novel features of the invention will become apparent to those skilled in the art upon examination of the detailed description and drawings that follow.